%0 Journal Article %A Duda, Jaromír %T Congruence restrictions on axes %J Mathematica Bohemica %D 1992 %P 251-258 %V 117 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.21136/MB.1992.126285/ %R 10.21136/MB.1992.126285 %G en %F 10_21136_MB_1992_126285